chardev/char-fe.c

   1 /*
   2  * QEMU System Emulator
   3  *
   4  * Copyright (c) 2003-2008 Fabrice Bellard
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23  */
  24 #include "qemu/osdep.h"
  25 #include "qemu/error-report.h"
  26 #include "qapi/error.h"
  27 #include "qapi-visit.h"
  28 #include "sysemu/replay.h"
  29
  30 #include "chardev/char-fe.h"
  31 #include "chardev/char-io.h"
  32 #include "chardev/char-mux.h"
  33
  34 int qemu_chr_fe_write(CharBackend *be, const uint8_t *buf, int len)
  35 {
  36     Chardev *s = be->chr;
  37
  38     if (!s) {
  39         return 0;
  40     }
  41
  42     return qemu_chr_write(s, buf, len, false);
  43 }
  44
  45 int qemu_chr_fe_write_all(CharBackend *be, const uint8_t *buf, int len)
  46 {
  47     Chardev *s = be->chr;
  48
  49     if (!s) {
  50         return 0;
  51     }
  52
  53     return qemu_chr_write(s, buf, len, true);
  54 }
  55
  56 int qemu_chr_fe_read_all(CharBackend *be, uint8_t *buf, int len)
  57 {
  58     Chardev *s = be->chr;
  59     int offset = 0, counter = 10;
  60     int res;
  61
  62     if (!s || !CHARDEV_GET_CLASS(s)->chr_sync_read) {
  63         return 0;
  64     }
  65
  66     if (qemu_chr_replay(s) && replay_mode == REPLAY_MODE_PLAY) {
  67         return replay_char_read_all_load(buf);
  68     }
  69
  70     while (offset < len) {
  71     retry:
  72         res = CHARDEV_GET_CLASS(s)->chr_sync_read(s, buf + offset,
  73                                                   len - offset);
  74         if (res == -1 && errno == EAGAIN) {
  75             g_usleep(100);
  76             goto retry;
  77         }
  78
  79         if (res == 0) {
  80             break;
  81         }
  82
  83         if (res < 0) {
  84             if (qemu_chr_replay(s) && replay_mode == REPLAY_MODE_RECORD) {
  85                 replay_char_read_all_save_error(res);
  86             }
  87             return res;
  88         }
  89
  90         offset += res;
  91
  92         if (!counter--) {
  93             break;
  94         }
  95     }
  96
  97     if (qemu_chr_replay(s) && replay_mode == REPLAY_MODE_RECORD) {
  98         replay_char_read_all_save_buf(buf, offset);
  99     }
 100     return offset;
 101 }
 102
 103 int qemu_chr_fe_ioctl(CharBackend *be, int cmd, void *arg)
 104 {
 105     Chardev *s = be->chr;
 106     int res;
 107
 108     if (!s || !CHARDEV_GET_CLASS(s)->chr_ioctl || qemu_chr_replay(s)) {
 109         res = -ENOTSUP;
 110     } else {
 111         res = CHARDEV_GET_CLASS(s)->chr_ioctl(s, cmd, arg);
 112     }
 113
 114     return res;
 115 }
 116
 117 int qemu_chr_fe_get_msgfd(CharBackend *be)
 118 {
 119     Chardev *s = be->chr;
 120     int fd;
 121     int res = (qemu_chr_fe_get_msgfds(be, &fd, 1) == 1) ? fd : -1;
 122     if (s && qemu_chr_replay(s)) {
 123         error_report("Replay: get msgfd is not supported "
 124                      "for serial devices yet");
 125         exit(1);
 126     }
 127     return res;
 128 }
 129
 130 int qemu_chr_fe_get_msgfds(CharBackend *be, int *fds, int len)
 131 {
 132     Chardev *s = be->chr;
 133
 134     if (!s) {
 135         return -1;
 136     }
 137
 138     return CHARDEV_GET_CLASS(s)->get_msgfds ?
 139         CHARDEV_GET_CLASS(s)->get_msgfds(s, fds, len) : -1;
 140 }
 141
 142 int qemu_chr_fe_set_msgfds(CharBackend *be, int *fds, int num)
 143 {
 144     Chardev *s = be->chr;
 145
 146     if (!s) {
 147         return -1;
 148     }
 149
 150     return CHARDEV_GET_CLASS(s)->set_msgfds ?
 151         CHARDEV_GET_CLASS(s)->set_msgfds(s, fds, num) : -1;
 152 }
 153
 154 void qemu_chr_fe_accept_input(CharBackend *be)
 155 {
 156     Chardev *s = be->chr;
 157
 158     if (!s) {
 159         return;
 160     }
 161
 162     if (CHARDEV_GET_CLASS(s)->chr_accept_input) {
 163         CHARDEV_GET_CLASS(s)->chr_accept_input(s);
 164     }
 165     qemu_notify_event();
 166 }
 167
 168 void qemu_chr_fe_printf(CharBackend *be, const char *fmt, ...)
 169 {
 170     char buf[CHR_READ_BUF_LEN];
 171     va_list ap;
 172     va_start(ap, fmt);
 173     vsnprintf(buf, sizeof(buf), fmt, ap);
 174     /* XXX this blocks entire thread. Rewrite to use
 175      * qemu_chr_fe_write and background I/O callbacks */
 176     qemu_chr_fe_write_all(be, (uint8_t *)buf, strlen(buf));
 177     va_end(ap);
 178 }
 179
 180 Chardev *qemu_chr_fe_get_driver(CharBackend *be)
 181 {
 182     return be->chr;
 183 }
 184
 185 bool qemu_chr_fe_init(CharBackend *b, Chardev *s, Error **errp)
 186 {
 187     int tag = 0;
 188
 189     if (CHARDEV_IS_MUX(s)) {
 190         MuxChardev *d = MUX_CHARDEV(s);
 191
 192         if (d->mux_cnt >= MAX_MUX) {
 193             goto unavailable;
 194         }
 195
 196         d->backends[d->mux_cnt] = b;
 197         tag = d->mux_cnt++;
 198     } else if (s->be) {
 199         goto unavailable;
 200     } else {
 201         s->be = b;
 202     }
 203
 204     b->fe_open = false;
 205     b->tag = tag;
 206     b->chr = s;
 207     return true;
 208
 209 unavailable:
 210     error_setg(errp, QERR_DEVICE_IN_USE, s->label);
 211     return false;
 212 }
 213
 214 void qemu_chr_fe_deinit(CharBackend *b)
 215 {
 216     assert(b);
 217
 218     if (b->chr) {
 219         qemu_chr_fe_set_handlers(b, NULL, NULL, NULL, NULL, NULL, true);
 220         if (b->chr->be == b) {
 221             b->chr->be = NULL;
 222         }
 223         if (CHARDEV_IS_MUX(b->chr)) {
 224             MuxChardev *d = MUX_CHARDEV(b->chr);
 225             d->backends[b->tag] = NULL;
 226         }
 227         b->chr = NULL;
 228     }
 229 }
 230
 231 void qemu_chr_fe_set_handlers(CharBackend *b,
 232                               IOCanReadHandler *fd_can_read,
 233                               IOReadHandler *fd_read,
 234                               IOEventHandler *fd_event,
 235                               void *opaque,
 236                               GMainContext *context,
 237                               bool set_open)
 238 {
 239     Chardev *s;
 240     ChardevClass *cc;
 241     int fe_open;
 242
 243     s = b->chr;
 244     if (!s) {
 245         return;
 246     }
 247
 248     cc = CHARDEV_GET_CLASS(s);
 249     if (!opaque && !fd_can_read && !fd_read && !fd_event) {
 250         fe_open = 0;
 251         remove_fd_in_watch(s);
 252     } else {
 253         fe_open = 1;
 254     }
 255     b->chr_can_read = fd_can_read;
 256     b->chr_read = fd_read;
 257     b->chr_event = fd_event;
 258     b->opaque = opaque;
 259     if (cc->chr_update_read_handler) {
 260         cc->chr_update_read_handler(s, context);
 261     }
 262
 263     if (set_open) {
 264         qemu_chr_fe_set_open(b, fe_open);
 265     }
 266
 267     if (fe_open) {
 268         qemu_chr_fe_take_focus(b);
 269         /* We're connecting to an already opened device, so let's make sure we
 270            also get the open event */
 271         if (s->be_open) {
 272             qemu_chr_be_event(s, CHR_EVENT_OPENED);
 273         }
 274     }
 275
 276     if (CHARDEV_IS_MUX(s)) {
 277         mux_chr_set_handlers(s, context);
 278     }
 279 }
 280
 281 void qemu_chr_fe_take_focus(CharBackend *b)
 282 {
 283     if (!b->chr) {
 284         return;
 285     }
 286
 287     if (CHARDEV_IS_MUX(b->chr)) {
 288         mux_set_focus(b->chr, b->tag);
 289     }
 290 }
 291
 292 int qemu_chr_fe_wait_connected(CharBackend *be, Error **errp)
 293 {
 294     if (!be->chr) {
 295         error_setg(errp, "missing associated backend");
 296         return -1;
 297     }
 298
 299     return qemu_chr_wait_connected(be->chr, errp);
 300 }
 301
 302 void qemu_chr_fe_set_echo(CharBackend *be, bool echo)
 303 {
 304     Chardev *chr = be->chr;
 305
 306     if (chr && CHARDEV_GET_CLASS(chr)->chr_set_echo) {
 307         CHARDEV_GET_CLASS(chr)->chr_set_echo(chr, echo);
 308     }
 309 }
 310
 311 void qemu_chr_fe_set_open(CharBackend *be, int fe_open)
 312 {
 313     Chardev *chr = be->chr;
 314
 315     if (!chr) {
 316         return;
 317     }
 318
 319     if (be->fe_open == fe_open) {
 320         return;
 321     }
 322     be->fe_open = fe_open;
 323     if (CHARDEV_GET_CLASS(chr)->chr_set_fe_open) {
 324         CHARDEV_GET_CLASS(chr)->chr_set_fe_open(chr, fe_open);
 325     }
 326 }
 327
 328 guint qemu_chr_fe_add_watch(CharBackend *be, GIOCondition cond,
 329                             GIOFunc func, void *user_data)
 330 {
 331     Chardev *s = be->chr;
 332     GSource *src;
 333     guint tag;
 334
 335     if (!s || CHARDEV_GET_CLASS(s)->chr_add_watch == NULL) {
 336         return 0;
 337     }
 338
 339     src = CHARDEV_GET_CLASS(s)->chr_add_watch(s, cond);
 340     if (!src) {
 341         return 0;
 342     }
 343
 344     g_source_set_callback(src, (GSourceFunc)func, user_data, NULL);
 345     tag = g_source_attach(src, NULL);
 346     g_source_unref(src);
 347
 348     return tag;
 349 }
 350
 351 void qemu_chr_fe_disconnect(CharBackend *be)
 352 {
 353     Chardev *chr = be->chr;
 354
 355     if (chr && CHARDEV_GET_CLASS(chr)->chr_disconnect) {
 356         CHARDEV_GET_CLASS(chr)->chr_disconnect(chr);
 357     }
 358 }